Among the announcements made by Apple today at the iPhone OS 3.0 preview event was newly-touted accessory compatibility for the updated OS. Using new APIs made available in the iPhone OS 3.0 SDK, accessory makers will be able to write custom applications that communicate directly with their hardware via the 30-pin Dock Connector or wirelessly over Bluetooth.
While Apple used both an on-screen speaker equalizer and an open-station finder for an FM transmitter as examples of this technology in use, it is possible for this new ability to open the door for third-party gaming accessories, however, Apple did not cite either this or support for keyboards as currently announced features of iPhone OS 3.0.
Apple has also added support for stereo Bluetooth using the A2DP protocol; this feature will work on the iPhone 3G for certain, but not on the original iPhone; it is likely to work on the iPod touch 2G as well, but not on the original iPod touch.
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